Dummies guide to fans and heatsinks.

Posted by: TCPMeta

Dummies guide to fans and heatsinks. - 11/29/06 09:53 PM

-=Topic one=- Fans

A lot of people think if they cram a lot of fans into their system it will make it cooler. Yes but at the same time you have to think about the Power supply wattage and also you need to know how many CFM the fan/s you are going to install. A lot of people are sold by a fan because of the bearings, lightup and how many volts it uses. Well a bearing is a bearing as long as it is lubed and no water touches it. A 5 volt fan can do just as well as a 12 volt fan. What you have to look for is how many CFMs it pushes air. Lower the CFMs the fan pushes the more quite is it. At the same time less air gets pushed or sucked. Higher is better yet it's louder For a example I have a 80mm Vantec Tornado Case Fan that pushes 84.1 CFM at 5700 RPM but the DB Noise is 55.2. Pretty damn loud if you ask me but I like to have some white noise going on when I sleep.
Heres a small tip on when looking for fans.

How is a case fan measured?
A case fan is simply measured by the width and length of the frame of the case fan. An 80mm case fan's frame for example is 80mm wide and 80mm long. It is not measured like a TV (diagonal) or from screw hole to screw hole.

Is DB the only way to measure fan volume?
DB is a simple measure of sound pressure. The human ear picks up frequencies differently. A 1K frequency will sound louder than a 50 frequency, just think of music where a bass beat can be played very loud and doesn't ring your ears while a guitar riff will spilt your head at the same volume. These frequencies apply with different fan motors as well.

What does CFM mean?
"Cubic feet per minute" A rating that expresses the amount of air a blower or fan can move. The volume of air that can pass through an opening in one minute.


-= Topic Two =- Heat sinks
Back in the old days of computers we didn't need heatsinks. Heatsinks started to apear when systems got faster, like the late 386 and up and for RISC "PPC" based CPUs the 68040 (I think I got that right.) With out them the CPU, CPU or even memory would over heat and die. Ofcorse over time people have found out you can overclock CPUs and think i'll just pop on a bigger heatsink. It works but sometimes it doesn't. You can have a hetsink that is big as your head and it can not do a damn thing to keep the CPU, GPU or memory cool. Heatsinks are mass produced out of molds. If you look at a heatsink you can see defects like a scratch or something. That scratch can be deadly, not right away but overtime. Most of the time you hear about diffrent thermal pastes that help make CPUs and heatsinks work better for cooling. All this does is to fill the gaps/scratches in the heatsink and sometimes the CPU,GPU or memory. Thing is this is only a temporary (Well is use to be a temporary thing). Back in the day heatsinks would be painted and all over including the side where it rests onto the CPU, GPU or memory. A lot of people just sanded it off or left it.

What you should do if you plan to overclock or fix a overheating issue is to drop the thermal pastes and lap the heatsink and sometimes the CPU, GPU or memory depending hat it is made out of by sanding it. This is known as lapping. You sand it so much it because a mirror finish meaning no scratches or gaps. Heres a link to a site that has a guide if you shall ever try it. http://www.overclockersclub.com/guides/heatsinklappingguide.php I have done this myself with a heatsink for a PC I use to own then gave it to my mother. Like I said there are some dies out there that can be sanded but I wouldn't sand a plain old slicon chip.

The reason why I have posted this is because I got finished dealing with 3 clients today that overkilled their systems with fans and big and i mean big heatsinks and still running into overheating problems. Heck I told them to just buy two high CFM fans and also get a heatsink that is lapped or I could do it for 50 bucks and they said the following " the fans are too loud, and what is lapping?" If you have 12 low CFM fans in the system it is already loud and lapping is sanding the heatsink to a mirror finish to take off the defects in the heatsink's metal.
Posted by: manhackman

Re: Dummies guide to fans and heatsinks. - 12/02/06 09:51 AM

This was posted just as I started reading up on cooling! And I am also a dummy! perfect!!!!! :P
Posted by: TCPMeta

Re: Dummies guide to fans and heatsinks. - 12/04/06 06:15 PM

LOL!!!

Not saying everyone is a dummy with cooling. Just need to know a bit more then what most people do.